Lens strap structure



Oct. 10, 1939. ow s 2,175,355

LENS STRAP STRUCTURE Filed Sept. 10, 1938 1 r Illlll I I lgm um 57 /0 if5 .30 g 5 7 /0 1 u|1|\\ is INVENT OR.

. ATTORNEY.

Patented Oct. 10, 1939 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to improvements in lens strap connections forophthalmic mountings; and the invention has reference, moreparticularly, to a novel strap structure for supporting lenses inconnection with various desired elements of a rimless ophthalmicmounting, as e. g. in connection with the center piece or bridge, noseguards, temple pivoting end pieces, etc.

This invention has for its objects to provide a novel lens strapstructure which is self-adjusting to any thickness of lens; which lookssecurely against loosening when secured to the lens; and which is ofneat and attractive appearance, being provided with a fastening screwmeans having a slotless head which countersinks flush to the face of theexternal strap plate when in place, and which is thus subject to beingengraved in conjunction with said strap plate face so as to beindiscernible.

Other objects of this invention, not at this time more particularlyenumerated, will be understood from the following detailed descriptionof the same.

Fig. 1 is a fragmentary front face view of an 25 ophthalmic mounting andlens equipped with the novel lens strap structure according to thisinvention; Fig. 2 is a rear face view of the same; Fig. 3 is a top edgeview of the lens strap structure drawn on an enlarged scale; Fig. 4 is alongitudinal horizontal section assembled, and Fig. 5 is a similarsection disassembled; Fig. 6 is an exterior face view of the front plateof the strap structure; and Fig. '7 is an interior face view of the rearplate of the strap structure.

Similar characters of reference are employed in the above describedviews, to indicate corresponding parts.

Referring to the drawing, the reference character Ill indicates thefront plate of the strap structure, the same having integrally formed atone end thereof an angular butt portion l l adapted to extend across theedge of a lens L to which the strap structure is to be applied.Extending in opposite directions respectively from the upper and undersides of said butt portion II are arouate strap portions I2 adapted toengage the adjustment edge of the lens L. A desired element of a rimlessophthalmic mounting is suitably secured to the butt portion II. Inillustration of this, there is shown in Fig. 1, a center piece or bridgel3 so secured to said butt portion II, but it will be understood thatother elements such as nose guards, temple end pieces, etc., may," whendesired, be connected with the strap structure of this invention in likeor in any other suitable manner.

The front plate of the strap structure I0 is provided with a suitablyshaped perforation or opening for operative alignment with an opening 5M with which the lens L is provided, to receive therethrough a suitablescrew-threaded fastening stud l5. This fastening stud I5 is providedwith a head [6 having a male interlocking portion I l of square or otherselected polygonal cross sectional shape, and said head is furtherprovided outwardly of said interlocking portion IT with a circular headpiece I8. The perforation provided in the front plate Ill is shaped toconform to the head iii of said fastening stud l5, and so that said headl6 countersinks therein flush with the external face surface of saidfront plate l0. Illustrative of this said front plate perforationcomprises an inner squaresocket [9 to correspond to and receive saidsquare interlocking portion [1 of the stud l5, and an outer circularsocket 211 to correspond to and receive the circular head piece l8 ofthe stud, whereby said stud, when operatively assembled with the frontplate I0 is interlocked therewith against relative rotation, while atthe same time the head is countersunk flush with the external facesurface of the front plate I0. This latter arrangement substantiallyconceals the stud l 5, especially when the external face of the frontplate I0 is engraved, and consequently permits of a very neat andattractive appearance of the obverse side of the strap structure whenthe latter is operatively incorporated in an ophthalmic mounting.

The reference character 2| indicates the rear plate of the strapstructure. This rear plate is a separable element of the strapstructure, and is provided with a notched rearward end portion, thenotch 22 of which constitutes a female coupling element adapted tocooperate with a 40 laterally projecting lug 23 with which the buttportion H of the front plate I0 is provided, said lug 23 constitutingthe cooperative male coupling element.

Rotatably mounted in connection with the body 45 of said rear plate 2!is a nut member comprising a journal portion 24 having an outer annularkeeper flange 25. Said journal portion 24 is rotatably supported in abearing opening 26 with which the rear plate 2| is provided, saidbearing opening having a diametrically enlarged outer portion 21 toreceive said keeper flange 25, thus forming a shoulder 28 engaged bysaid flange 25 so that inward axial displacement of said nut member isprevented. The inner face of said rear plate 2| is formed with acountersunk chamber 29. The inner end of said journal portion 24 isbeaded over within said chamber 29 to provide a second keeper flange 30bearing against the bottom of said chamber 29 so that outward axialdisplacement of said nut member is prevented. At its outer end said nutmember is provided with a head 3| of square or other selected polygonalshape. The nut member is provided with an internally screw-threadedaxial bore 32. It will be obvious that the nut member has a permanentswiveled relation to said rear plate 2|.

In applying the novel strap structure to a lens L, the front plate I isapplied over the front face of said lens, with the arcuate strapportions l2 abutting the lens edge. As thus disposed the perforation oropening of the front plate will align itself with the opening M of thelens L, whereupon the stud I5 is inserted through these parts with itshead l6 countersunk in the body of said front plate as above described.Therear plate 2| is thereupon opposed to the rear face of the lens L andits nut member aligned with the stud I5, whereupon said swiveling nutmember is rotated, by means of a suitable Wrench .tool (not shown), tocause the same to screw over and down upon said stud |5, thus drawingdown upon the rear face of the lens L said rear plate 2|. As the rearplate 2| is thus tightened home, its notched end 22 will move intostraddling relation to the lug 23 carried by the front plate butt, andwill thus interlock with the latter so as to be retained aligned withthe front plate I0 and against r0- tative displacement.

It will be obvious that a very simple, easily manipulated and appliedstrap structure is provided by this invention, whereby, owing to thebodily movement relative to the front plate I!) of which the rear plate2| is capable, the said strap structure is self adjusting to variousthicknesses of lenses, and wherein, when applied to a lens, the strapplates will respectively engage flatly against the lens faces withoutsetting up unequal pressures or stresses in lens, and conse= quentlyeliminating risk of lens fracture due to such causes.

In addition to its mechanical advantages, the novel lens strap structureis such that its obverse side is free from unsightly projecting screwheads or like protuberances, the same presenting a smooth face which maybe decoratively engraved, thus concealing even the lines of jointbetween the same and the stud head l6.

Having thus described my invention, I claim:

1. A lens strap structure for ophthalmic mountings comprising, a frontplate and a rear plate between which a lens is receivable, anonrotatable screw-threaded stud to extend through an engaged lens fromsaid front plate, said rear plate having a chambered inner face, saidrear plate also having a bearing opening leading outwardly from saidchambered inner face thereof and provided with a diametrically enlargedouter portion, a swivel nut member carried by said rear plate to engagesaid stud, said nut member having a journal portion mounted in saidbearing opening and a keeper flange seated in the en larged outer endportion of the latter, the inner end of said journal portion having asecond keeper flange disposed in the chambered inner face of said rearplate, and the outer end of said nut member having a squared headprojecting beyond the outer face of said rear plate.

2. A lens strap structure for ophthalmic mountings comprising, a frontplate having lens edge abutting means at one end thereof, ascrewthreaded stud to extend through an engaged lens from said frontplate, said stud having a head countersunk in said front plate flushwith the outer face thereof, cooperative means on said stud head andfront plate for interlocking the stud and front plate against relativerotation, a separable rear plate having a chambered inner face, saidrear plate having a bearing opening leading outwardly from saidchambered inner face thereof and provided with a diametrically enlargedouter end portion, a swivel nut member carried by said rear plate toengage said stud, said nut member having a journal portion mounted insaid bearing opening and a keeper flange seated in the enlarged outerend portion of the latter, the inner end of said journal portion havinga second keeper flange disposed in the chambered inner face of said rearplate, the outer end of said nut member having a squared head projectingbeyond the outer face of said rear plate, a laterally projecting lugextending rearwardly from the lens and abutting means of said frontplate, and said rear plate having a notched end portion to straddle saidlug to thereby retain said rear plate against rotative displacement whenassembled with said front plate and a served lens.

1 BERT J. LOWRES.

